Display panel and method for narrowing edges and increasing edge strength thereof

ABSTRACT

An edge narrowing method for a display panel is disclosed. The display panel includes a first substrate, a second substrate, a sealant and a light-shielding area. The sealant is disposed between the first substrate and the second substrate. The light-shielding area is disposed between the first substrate and the sealant. The method includes the steps of providing the display panel, a grinding apparatus and a polishing apparatus; tilting the display panel so that the first substrate and a grinding member of the grinding apparatus have a first grinding angle therebetween; grinding the first substrate and the light-shielding area with the grinding apparatus while the display panel is tilted at the first grinding angle, thereby forming a first grinding end surface; stopping grinding of the first substrate and the light-shielding area when the width of the light-shielding area is between 0.35 and 1 mm; and polishing the first grinding end surface with the polishing apparatus to form a first end surface.

BACKGROUND OF THE INVENTION

(A) Field of the Invention

The present invention relates to display panel technologies, and morespecifically, to a liquid crystal display panel and methods fornarrowing edges and increasing edge strength thereof.

(B) Description of Related Art

Liquid crystal displays (LCD) have many advantages such as thin profile,light weight, low power consumption and low radiation, and therefore arewidely used in current display applications. An LCD display primarilyincludes an LCD panel and a back light unit. The back light unit servesas an illumination source for the LCD panel, and the rotations of theliquid crystals are controlled by electrical signals so as to displayimages.

As the technology of portable mobile apparatus advances, in order tomeet demands of artistic appearance and miniature size, the side framesof the display panel need to be narrowed. However, the requirements arenot met by means of narrowing the design only. The panel strength needsto be considered when the side frames are narrowed, which makes thenarrowing process relatively difficult.

Therefore, there is high demand to narrow the display panel edges andsustain the strength of the side frames to avoid panel damage.

SUMMARY OF THE INVENTION

In order to resolve the above problems, the present invention provides adisplay panel and methods for narrowing edges and increasing edgestrength, so as to effectively narrow the side frames of the displaypanel and increase the strength of side frames to meet the demand ofnarrowing edges of the display panel.

According to a first embodiment of the present invention, a method fornarrowing edges of a display panel is disclosed. The display panelincludes a first substrate, a second substrate, a sealant and alight-shielding area, the sealant being disposed between the firstsubstrate and the second substrate, the light-shielding area beingdisposed between the sealant and the first substrate. The method fornarrowing edges includes the steps of providing the display panel, agrinding apparatus and a polishing apparatus; tilting the display panelso that the first substrate and a grinding member of the grindingapparatus form a first grinding angle; grinding the first substrate andthe light-shielding area with the grinding apparatus to form a firstgrinding end surface on the first substrate while the display panel istilted at the first grinding angle; stopping grinding of the firstsubstrate and the light-shielding area when the width of thelight-shielding area is between 0.35 and 1 mm; and polishing the firstgrinding end surface with the polishing apparatus to form a first endsurface. Moreover, the second substrate or the sealant may be ground andpolished while the display panel is tilted at the first tilt angle;alternatively, the display panel is tilted so that the display panel andthe grinding apparatus form a second grinding angle. The secondsubstrate and/or the sealant may be ground and polished while thedisplay panel is tilted at the second grinding angle.

According to a second embodiment of the present invention, a method forincreasing edge strength of a display panel is disclosed. The displaypanel includes a first substrate, a second substrate and a sealant, thesealant being disposed between the first substrate and the secondsubstrate. The method for increasing edge strength includes the steps ofproviding the display panel, a grinding apparatus and a polishingapparatus; tilting the display panel so that the second substrate of thedisplay panel and a grinding member of the grinding apparatus form agrinding angle; grinding the second substrate with the grindingapparatus to form a grinding end surface on the second substrate whilethe display panel is tilted at the grinding angle; and polishing thegrinding end surface with the polishing apparatus to form an endsurface.

According to a third embodiment of the present invention, a displaypanel includes a first substrate, a second substrate and a sealant. Thefirst substrate includes a first outer surface, a first inner surfaceand a first end surface, the first outer surface and the first endsurface having a first included angle therebetween. The second substrateis disposed opposite to the first substrate and includes a second outersurface, a second inner surface and a second end surface, the secondouter surface and the second end surface having a second included angletherebetween. The sealant is disposed between the first inner surfaceand the second inner surface, and includes a sealant end surface betweenthe first end surface and the second end surface. The arithmetic averageroughness Ra of the first end surface or the second end surface isbetween 0.001 and 0.04 μm, and the maximum roughness height Ry of thefirst end surface or the second end surface is between approximately 0.1and 0.5 μm. In an embodiment, the first included angle is between 95 and110 degrees.

According to a fourth embodiment of the present invention, a displaypanel includes a first substrate, a second substrate, a sealant and alight-shielding area. The first substrate includes a first inner surfaceand a first end surface. The second substrate is disposed opposite tothe first substrate and includes a second inner surface and a second endsurface. The sealant is disposed between the first inner surface and thesecond inner surface, and includes a sealant end surface between thefirst end surface and the second end surface. The light-shielding areais disposed between the first inner surface and the sealant, andincludes an outer end surface and an inner end surface. The outer endsurface is connected to the first end surface and the sealant endsurface, and the outer end surface and the inner end surface areseparated by a minimum distance between 0.35 and 1 mm.

According to a fifth embodiment of the present invention, a method fornarrowing edges of a display panel is disclosed. The display panelincludes a first substrate, a second substrate, a sealant, an initialfirst photo spacer, a second photo spacer and a liquid crystal layer,the initial first photo spacer and the second photo spacer forming atrench at an edge of the first substrate, the initial first photo spacerbeing placed outside the sealant and far from the liquid crystal layer,the second photo spacer being placed inside the sealant and next to theliquid crystal layer, the sealant and the liquid crystal layer beingplaced between the first substrate and the second substrate, and thesealant being within the trench. The method for narrowing edges includesthe steps of providing the display panel and a cutting apparatus; andsimultaneously cutting the first substrate, the initial first sensingspacer and the second substrate with the cutting apparatus to form afirst photo spacer and an end surface, the end surface going through thefirst substrate, the first photo spacer and the second substrate.

According to a sixth embodiment of the present invention, a displaypanel includes a first substrate, a second substrate disposed oppositeto the first substrate, a liquid crystal layer, a first photo spacer, asecond photo spacer and a sealant. The liquid crystal layer is disposedbetween the first substrate and the second substrate. The first photospacer is disposed on the first substrate and between the firstsubstrate and the second substrate. The second photo spacer is disposedon the first substrate and between the first substrate and the secondsubstrate, and the second photo spacer and the first photo spacer form atrench therebetween. The sealant is disposed between the first substrateand the second substrate and within the trench. The first photo spaceris placed outside the sealant and far from the liquid crystal layer, andthe second photo spacer is placed inside the sealant and next to theliquid crystal layer. The first photo spacer and the first substrate andthe second substrate at a corresponding position form an end surfacegoing through the first substrate, the first photo spacer and the secondsubstrate.

In view of the above panel structure, the present invention discloses adisplay panel including a first substrate, a second substrate and aliquid crystal confined structure. The first substrate includes a firstouter surface, a first inner surface and a first end surface, the firstouter surface and the first end surface having a first included angletherebetween. The second substrate is disposed opposite to the firstsubstrate and includes a second outer surface, a second inner surfaceand a second end surface, the second outer surface and the second endsurface having a second included angle therebetween. The liquid crystalconfined structure is disposed between the first inner surface and thesecond inner surface, and includes a liquid crystal confined structureend surface between the first end surface and the second end surface.The arithmetic average roughness Ra of the first end surface or thesecond end surface is between 0.001 and 0.04 μm, and the maximumroughness height Ry of the first end surface or the second end surfaceis between around 0.1 and 0.5 μm.

The liquid crystal confined structure may include the sealant, or thefirst photo spacer, the second photo spacer and the sealant between thefirst photo spacer and the second photo spacer.

According to the display panel and the methods for narrowing edges andincreasing edge strength of the present invention, the width of the sideframes can be decreased to between 0.35 mm and 1 mm, and the strengthloss problem caused by edge narrowing can be effectively resolved.Therefore, the present invention is practical.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a top view of a display panel;

FIG. 2 shows the cross-sectional view along line 1-1 of FIG. 1;

FIGS. 3 and 4 show a grinding process for narrowing edges of the displaypanel in accordance with an embodiment of the present invention;

FIGS. 5 and 6 show a grinding process for narrowing edges of the displaypanel in accordance with another embodiment of the present invention;

FIGS. 7 and 8 show the display panels through uneven grinding andpolishing in accordance with the present invention;

FIG. 9 shows a top view of the display panel after edge narrowing inaccordance with the present invention;

FIGS. 10 and 11 show a polishing process for narrowing edges of thedisplay panel in accordance with an embodiment of the present invention;

FIGS. 12 and 13 show a polishing process for narrowing edges of thedisplay panel in accordance with another embodiment of the presentinvention;

FIG. 14 shows the strengths of the display panel after grinding andpolishing;

FIGS. 15 to 17 show a display panel and the method for narrowing edgesthereof in accordance with another embodiment of the present invention;

FIG. 18 shows a polishing process for narrowing edges of the displaypanel in accordance with another embodiment of the present invention;

FIG. 19 shows a display panel in accordance with another embodiment ofthe present invention; and

FIGS. 20 and 21 show the display panels through uneven grinding andpolishing in accordance with another embodiment of the presentinvention.

DETAILED DESCRIPTION OF THE INVENTION

The making and use of the presently preferred embodiments are discussedin detail below. It should be appreciated, however, that the presentinvention provides many applicable inventive concepts that can beembodied in a wide variety of specific contexts. The specificembodiments discussed are merely illustrative of specific ways to makeand use the invention, and do not limit the scope of the invention.

The display panel and the methods for narrowing edges and increasingedge strength of the present invention are described with appendeddrawings below.

The method for narrowing edges of a display panel is stated as follows:FIG. 1 shows a top view of a display panel 10 including three firstsides 11 and a second side 12. The second side 12 is used for connectingthe circuits (not shown) in the display panel to external circuit boards(not shown). The three first sides 11 and the second side 12 aremutually connected. A light-shielding area 13 close to the first sides11 and the second side 12 is formed, and may use the same material asblack matrix or may be formed with the black matrix at the same time.The edge narrowing of the present invention is applied to the firstsides 11, and is exemplified below.

FIG. 2 shows a cross-sectional view of line 1-1 of FIG. 1. The displaypanel 10 includes a first substrate 21, a second substrate 22 and asealant 23 (liquid crystal confined structure). In an embodiment, thefirst substrate 21 may be a color filter array substrate (CF substrate),and the second substrate 22 may be a thin film transistor arraysubstrate (TFT substrate). Alternatively, the first substrate 21 may bea thin film transistor array substrate, and the second substrate 22 maybe a color filter array substrate. The light-shielding area 13 isdisposed below the first substrate 21 including color filter array (notshown), and approximately corresponds to the sealant 23. The sealant 23is disposed between the first substrate 21 and the second substrate 22,and the light-shielding area 13 with a width w is disposed between thesealant 23 and the first substrate 21. The width of side frame isdenoted by w′, which is from the inner edge of the light-shielding area13 to the outer edge of the first substrate 21 and/or the secondsubstrate 22.

Referring to FIG. 3, the display panel 10 is tilted, so that a firstgrinding angle θ1 is formed between the first substrate 21 and agrinding member 31 of a grinding apparatus 30, and θ1 is an acute angle.That is, the display panel 10 is tilted corresponding to the grindingmember 31 of the grinding apparatus 30; in other words, the displaypanel 10 is tilted. While the display panel 10 is tilted with the firstgrinding angle θ1, the first substrate 21 is ground by the grindingmember 31 of the grinding apparatus 30, and the light-shielding area 13is ground as well, so as to form a first grinding end surface 26 on thefirst substrate 21. In an embodiment, the first grinding angle θ1 may bebetween approximately 70 and 88 degrees, and is preferably between 78and 85 degrees. When the remaining width w″ of the light-shielding area13 is between approximately 0.35 and 1 mm, grinding of the firstsubstrate 21 and the light-shielding area 13 by the grinding apparatus30 is stopped. After grinding, the exceeding portion of the side framewidth w′ compared to the light-shielding area width w″ is removed, sothat the side frame width w′ is equivalent to the light-shielding areawidth w″, i.e., the side frame width w′ is between approximately 0.35and 1 mm. The first grinding end surface 26 has average roughness Rabetween 0.1 and 0.88 μm and maximum roughness height Ry between around0.93 and 8.5 μm.

In an embodiment, the grinding apparatus 30 continues to grind thesealant 23 and the second substrate 22 while the display panel 10 istilted at the first grinding angle θ1, and as a result the grounddisplay panel 10 appears as shown FIG. 4, in which the edges of thefirst substrate 21, the light-shielding area 13, the sealant 23 and thesecond substrate 22 are aligned in a common plane.

Referring to FIG. 5, in another embodiment, after grinding the firstsubstrate 21, the display panel 10 is tilted at another side, so thatthe second substrate 22 and the grinding apparatus 30 form a secondgrinding angle θ2 therebetween. That is, the display panel 10 is tiltedcorresponding to the grinding member 32 of the grinding apparatus 30; inother words, the display panel 10 is tilted. While the display panel 10is tilted at the first grinding angle θ2, the second substrate 22 isground by the second grinding member 32 of the grinding apparatus 30, soas to form a second grinding end surface 28 on the second substrate 22,as shown in FIG. 6. At this time, the side frame width w′ is equivalentto the light-shielding area width w″. The second grinding angle θ2 maybe between approximately 70 and 88 degrees, and is preferably between 78and 85 degrees. The ground second substrate 22 is shown in FIG. 6. Thesecond grinding end surface 28 has average roughness Ra between 0.1 and0.88 μm and maximum roughness height Ry between approximately 0.93 and8.5 μm.

More specifically, the grinding apparatus 30 may include the firstgrinding member 31 and the second grinding member 32. The first grindingmember 31 is used to grind the first substrate 21 and thelight-shielding area 13 or the sealant 23. The second grinding member 32is used to grind the second substrate 22 or the sealant 23. Accordingly,the first grinding member 31 and the second grinding member 32 can be ofdifferent designs, so that they are suitable but not limited forflexible manufacturing. In practice, the first substrate 21, the secondsubstrate 22, the light-shielding area 13 and the sealant 23 can beground by the same grinding member or other flexible combination.

FIG. 6 shows the equivalent grinding at two sides. In practice, unequalor uneven grinding at two sides is practical also as shown in FIG. 7 andFIG. 8.

Referring to FIG. 7, in the case of longer time or larger amount ofgrinding at the first grinding angle θ1, the grinding apparatus 30 cangrind the sealant 23 and a portion of the second substrate 22.Accordingly, the first grinding end surface 26 is from the firstsubstrate 21, the light-shielding area 13, and the sealant 23 to aportion of the second substrate 22. In contrast, the grinding time orthe grinding amount for grinding at the second grinding angle θ2 isless; thus the second grinding end surface 28 only includes anotherportion of the second substrate 22. An alternative is shown in FIG. 8,in the case of a shorter time or less amount of grinding at the firstgrinding angle θ1 and a longer time or larger amount of grinding at thesecond grinding angle θ2, the first grinding end surface 26 onlyincludes a portion of first substrate 21, and the second grinding endsurface 28 is from the second substrate 22, the sealant 23, and thelight-shielding area 13 to another portion of the first substrate 21.

Accordingly, the side frames of the display panel 10 can be narrowed. Inthis embodiment, one or more of the three first sides 11 can benarrowed, and the second side 12 is not narrowed because of the circuitsof the display panel, as shown in FIG. 9. The side frame width w′ can benarrowed to between 0.35 mm and 1 mm, and is equivalent to the width w″of the light-shielding area, so as to meet the requirement of narrowingedges. However, the grinding end surfaces 26 and 28 of the narrowed sideframe of a width w′ are rough, may easily resulting in stressconcentration at roughness defects of the end surfaces 26 and/or 28, andlower the strength of the first substrate 21 and/or the second substrate22 of the display panel 10. To resolve this problem, the grinding endsurfaces 26 and 28 are further subjected to polishing to decrease theroughness.

In FIG. 10, the first grinding end surface 26 shown in FIG. 4 ispolished by a first polishing member 51 of the polishing apparatus 50.As a result, a first end surface 36 is formed in the first substrate 21,an outer end surface 42 is formed in the light-shielding area 13, asealant end surface 34 is formed in the sealant 23, and a second endsurface 38 is formed in the second substrate 22 as shown in FIG. 11. Thearithmetic average roughness Ra of the first end surface 36 and/or thesecond end surface 38 is decreased to between 0.001 and 0.04 μm, and itsmaximum roughness height Ry is between approximately 0.1 and 0.5 μm.

As to the structure shown in FIG. 11, the display panel 10 includes thefirst substrate 21, the second substrate 22 and the sealant 23. Thefirst substrate 21 includes a first outer surface 14, a first innersurface 15 and the first end surface 36. The first outer surface 14 andthe first end surface 36 form a first included angle φ1. The secondsubstrate 22 is disposed corresponding to the first substrate 21 andincludes a second outer surface 17, a second inner surface 18 and thesecond end surface 38. The second outer surface 17 and the second endsurface 38 form a second included angle φ2. The sealant 23 is disposedbetween the first inner surface 15 and the second inner surface 18, andincludes a sealant end surface 34 between the first end surface 36 andthe second end surface 38. The arithmetic average roughness Ra of thefirst end surface 36 or the second end surface 38 is between 0.001 and0.04 μm, and the maximum roughness height Ry of the first end surface 36or the second end surface 38 is between approximately 0.1 and 0.5 μm.The second included angle φ2 is equal to the first grinding angle θ1,and thus φ2 is between 70 and 88 degrees, or preferably, between 78 and85 degrees. In this embodiment, the first end surface 36, the second endsurface 38 and the sealant end surface 34 are in a common plane. The sumof the first included angle φ1 and the second included angle φ2 isaround 180 degrees. Therefore, the first included angle φ1 is between 92and 110 degrees, or preferably, between 95 and 102 degrees.

In FIG. 12, in another embodiment, the first grinding end surface 26,the light-shielding area 13, the sealant 23 and/or the second grindingend surface 28 shown in FIG. 6 are polished by a second polishing member52 of the polishing apparatus 50. As a result, a first end surface 36 isformed in the first substrate 21, an outer end surface 42 is formed inthe light-shielding area 13, a sealant end surface 34 is formed in thesealant 23, and a second end surface 38 is formed in the secondsubstrate 22 as shown in FIG. 13. The arithmetic average roughness Ra ofthe first end surface 36 and/or the second end surface 38 is decreasedto between 0.001 and 0.04 μm, and its maximum roughness height Ry isbetween approximately 0.1 and 0.5 μm.

As to the structure shown in FIG. 13, the display panel 10 includes thefirst substrate 21, the second substrate 22 and the sealant 23. Thefirst substrate 21 includes a first outer surface 14, a first innersurface 15 and the first end surface 36. The first outer surface 14 andthe first end surface 36 form a first included angle φ1. The secondsubstrate 22 is disposed corresponding to the first substrate 21 andincludes a second outer surface 17, a second inner surface 18 and thesecond end surface 38. The second outer surface 17 and the second endsurface 38 form a second included angle φ2 therebetween. The sealant 23is disposed between the first inner surface 15 and the second innersurface 18, and includes the sealant end surface 34 between the firstend surface 36 and the second end surface 38. The arithmetic averageroughness Ra of the first end surface 36 or the second end surface 38 isbetween 0.001 and 0.04 μm, and the maximum roughness height Ry of thefirst end surface 36 or the second end surface 38 is betweenapproximately 0.1 and 0.5 μm. The sum of the first included angle φ1 andthe first grinding angle θ1 is 180 degrees, and thus the first includedangle φ1 is between 92 and 110 degrees, or preferably, between 95 and102 degrees. Likewise, the sum of the second included angle φ2 and thesecond grinding angle θ2 is 180 degrees, and thus the second includedangle φ2 is between 92 and 110 degrees, or preferably, between 95 and102 degrees.

In FIG. 11 and FIG. 13, the light-shielding area 13 is disposed betweenthe first inner surface 15 and the sealant 23, and includes the outerend surface 42 and the inner end surface 44. The outer end surface 42 isconnected to the first end surface 36 or the sealant end surface 34. Theinner end surface 44 is disposed opposite to the outer end surface 42.The outer end surface 42 is distanced from the inner end surface 44 by aminimum width w″ (i.e., the remaining width of the light-shielding area)which is between 0.35 mm and 1 mm. Accordingly, the side frame width w′is equal to the remaining width w″ of the light-shielding area. In otherwords, the side frame width w′ is reduced to between 0.35 mm and 1 mm.In an embodiment, the first included angle φ1 is equal to the secondincluded angle φ2.

Likewise, the display panels shown in FIG. 7 and FIG. 8 can be furtherpolished. The first end surface 36, the sealant end surface 34 and aportion of the second end surface 38 are in a common plane, or thesecond end surface 38, the sealant end surface 34 and a portion of thefirst end surface 36 are in a common plane, so as to decrease the groundsurface roughness. Because the above description is a simple polishingprocess for those shown in FIG. 7 and FIG. 8, no further figures areillustrated for explanation.

In another embodiment, to increase the edge strength of the displaypanel 10 and the easiness of the process, only the second substrate 22(thin-film transistor substrate) is subjected to grinding and polishing,and the first substrate 21 is not ground or polished. The display panel10 is tilted so that the second substrate 22 and the grinding apparatus30 form a grinding angle therebetween. Sequentially, the grindingapparatus 30 grinds the second substrate 22 to form a grinding endsurface 28 on the second substrate 22 while the display panel 10 istilted at the grinding angle. The grinding end surface 28 is polished bythe polishing apparatus 50 to form an end surface 38.

FIG. 14 is the test result of display panel strength according toAmerican Society for Testing and Materials (ASTM) C158-02, in which thevertical axis is kilograms when the display panel is broken by applyinga force, with higher values indicating higher strength, and thehorizontal axis is listing the sample status. The test result shows thestrength of the side frames after grinding is decreased by around 13%,e.g., the side frame strength is decreased from 3.8 kg to 3.3 kg,whereas the strength of the side frame after polishing is increased byaround 51%, e.g., the side frame strength is increased from 3.8 kg to5.74 kg. This demonstrates that the polishing can effectively increasethe side frame strength.

In addition to the above, the present invention further proposes anothermethod for narrowing edges as follows. Referring to FIG. 15, a displaypanel 60 and a cutting apparatus 70 are provided. The display panel 60includes a first substrate 61, a second substrate 62, a sealant 63, aninitial first photo spacer 64, a second photo spacer 65 and a liquidcrystal layer 66. The initial first photo spacer 64 and the second photospacer 65 form a trench 67 at a side of the first substrate 61. Theinitial first photo spacer 64 is placed outside the sealant 63 and isfar from the liquid crystal layer 66. The second photo spacer 65 isplaced inside the sealant 63 and is next to the liquid crystal layer 66.The sealant 63 and the liquid crystal layer 66 are placed between thefirst substrate 61 and the second substrate 62, and the sealant 63 iswithin the trench 67.

The initial first photo spacer 64, the first substrate 61 and the secondsubstrate 62 are cut by the cutting apparatus 70 to form a first photospacer 68 and an end surface 69 as shown in FIG. 16. The end surface 69goes through the initial first photo spacer 64, the first substrate 61and the second substrate 62. The first photo spacer 68 formed by cuttingthe initial first photo spacer 64 and the second substrate 62 constitutea first gap 71, and the second photo spacer 65 and the second substrate62 form a second gap 72.

In an embodiment, the display panel 60 or the cutting apparatus 70 istilted so that the first substrate 61 and the cutting apparatus 70 forma cutting angle θ3 as shown in FIG. 17. The cutting angle θ3 is between70 and 88 degrees. The distance between the first photo spacer 68 andthe liquid crystal layer 66 is between 500 and 800 μm. The first gap 71or the second gap 72 is 0.5 to 2 μm. The first photo spacer 68 or thesecond photo spacer 65 has a width between 80 and 300 μm, and thesealant 63 may have a width between 400 and 700 μm.

Like the previous embodiment, in order to increase the strength, the endsurface 69 can be polished by a polishing apparatus 80. If there is notilt when cutting, the end surface 69 is polished directly. If the panelor the cutting apparatus is tilted when cutting, the display panel 60 orthe polishing apparatus 80 is tilted according to the cutting angle θ3,by which the first substrate 61 and the polishing apparatus 80 form apolishing angle θ4 therebetween, as shown in FIG. 18. The polishingangle θ4 is between 70 and 88 degrees.

As to the structure shown in FIG. 16, the display panel 60 includes afirst substrate 61, a second substrate 62 disposed opposite to the firstsubstrate 61, a liquid crystal layer 66 disposed between the firstsubstrate 61 and the second substrate 62, the first photo spacer 68, asecond photo spacer 65 and the sealant 63. The first photo spacer 68 isdisposed on the first substrate 61 and between the first substrate 61and the second substrate 62. The second photo spacer 65 is disposed onthe first substrate 61 and between the first substrate 61 and the secondsubstrate 62. A trench 67 is formed between the second photo spacer 65and the first photo spacer 68. The sealant 63 is formed between thefirst substrate 61 and the second substrate 62, and within the trench67. The first photo spacer 68 is placed outside the sealant 63 and isfar from the liquid crystal layer 66. The second photo spacer 65 isplaced inside the sealant 63 and is next to the liquid crystal layer 66.The first photo spacer 68, the first substrate 61 and the secondsubstrate 62 at a corresponding position form an end surface 69. The endsurface 69 goes through the first photo spacer 68, the first substrate61 and the second substrate 62.

FIG. 19 shows a display panel in accordance with another embodiment ofthe present invention. A display panel 90 includes a first substrate 61,a second substrate 62, a first photo spacer 68, a second photo spacer 65and a sealant 63 placed between the first photo spacer 68 and the secondphoto spacer 65. The first photo spacer 68, the second photo spacer 65and the sealant 63 may form a liquid crystal confined structure 100. Thefirst substrate 61 includes a first outer surface 91, a first innersurface 92 and a first end surface 75. The first outside surface 91 andthe first end surface 75 form a first included angle θ5. The secondsubstrate 62 is disposed opposite to the first substrate 61, andincludes a second outer surface 93, a second inner surface 94 and asecond end surface 76. The second outer surface 93 and the second endsurface 76 form a second included angle θ6. The liquid crystal confinedstructure 100 is formed between the first inner surface 92 and thesecond inner surface 94, and has a liquid crystal confined structure endsurface 110 between the first end surface 75 and the second end surface76. In this embodiment, the liquid crystal confined structure endsurface 110 is formed at the first photo spacer 68. After polishing, thearithmetic average roughness Ra of the first end surface 75 or thesecond end surface 76 is decreased to between 0.001 and 0.04 μm, and itsmaximum roughness height Ry is between approximately 0.1 and 0.5 μm.Preferably, the first included angle θ5 is between 90 and 110 degrees,and the second included angle θ6 is between 70 and 110 degrees.

FIG. 19 shows the case of equivalent grinding at two sides. In practice,unequal or uneven grinding and polishing at two sides is practical alsoas shown in FIG. 20 and FIG. 21.

In FIG. 20, the differences compared with FIG. 19 include the displaypanel 90 comprising the first end surface 75, the liquid crystalconfined structure end surface 110 and the second end surface 76. Thesecond end surface 76 is included in the second substrate 62. The firstend surface 75 goes from the first substrate 61, the liquid crystalconfined structure end surface 110 to a portion of the second substrate62. The first end surface 75 includes a portion of the first substrate61. In other words, the second end surface 76, the liquid crystalconfined structure end surface 110 and the portion of the first endsurface 75 are in a common plane.

In FIG. 21, the differences compared with FIG. 19 include the displaypanel 90 comprising the first end surface 75, the liquid crystalconfined structure end surface 110 and the second end surface 76. Thesecond end surface 76 is included in the second substrate 62. The firstend surface 75 goes from the first substrate 61, the liquid crystalconfined structure end surface 110 to a portion of the second substrate62. The second end surface 76 includes a portion of the second substrate62. In other words, the first end surface 75, the liquid crystalconfined structure end surface 110 and the portion of the second endsurface 76 are in a common plane.

The above grinding apparatus and polishing apparatus may use the same ordifferent machines. The grains for the grinding apparatus are largerthan the grains for the polishing apparatus. That is, the polishingapparatus can manufacture a surface with less roughness in comparisonwith the grinding apparatus. The grinding apparatus and the polishingapparatus are not restricted to the use of two different machines, andcan be the same machine by replacing grinding rollers or grinding tapesof different roughness.

The above-described embodiments of the present invention are intended tobe illustrative only. Numerous alternative embodiments may be devised bythose skilled in the art without departing from the scope of thefollowing claims.

1. A method for narrowing edges of a display panel, the display panelcomprising a first substrate, a second substrate, a sealant and alight-shielding area, the sealant being disposed between the firstsubstrate and the second substrate, the light-shielding area beingdisposed between the sealant and the first substrate, the methodcomprising: providing the display panel; tilting the display panel sothat the first substrate of the display panel and a horizontal planeform a first tilt angle therebetween; grinding the first substrate andthe light-shielding area to form a first grinding end surface on thefirst substrate and the light-shielding area while the display panel istilted at the first tilt angle; and polishing the first grinding endsurface to form a first end surface; wherein an arithmetic averageroughness Ra of the first end surface is between 0.001 and 0.04 μm, anda maximum roughness height Ry of the first end surface is betweenapproximately 0.1 and 0.5 μm.
 2. The method of claim 1, furthercomprising: grinding the second substrate or the sealant while thedisplay panel is tilted at the first tilt angle.
 3. The method of claim1, further comprising: tilting the display panel so that the secondsubstrate and the horizontal plane form a second tilt angletherebetween.
 4. The method of claim 3, further comprising: grinding thesecond substrate to form a second grinding end surface on the secondsubstrate while the display panel is tilted at the second tilt angle. 5.The method of claim 4, further comprising: grinding the sealant and aportion of the second substrate while the display panel is tilted at thefirst tilt angle.
 6. The method of claim 5, wherein the first grindingend surface goes from the first substrate, the light-shielding area, andthe sealant to the portion of the second substrate, and the secondgrinding end surface comprises a portion of the second substrate.
 7. Themethod of claim 4, further comprising: grinding the sealant and aportion of the first substrate while the display panel is tilted at thesecond tilt angle.
 8. The method of claim 4, wherein the second grindingend surface goes from the second substrate, the sealant, and thelight-shielding area to a portion of the first substrate.
 9. The methodof claim 1, further comprising: grinding the sealant while the displaypanel is tilted at the second tilt angle.
 10. The method of claim 1,further comprising: polishing the second grinding end surface to form asecond end surface, wherein an arithmetic average roughness Ra of thesecond end surface is between 0.001 and 0.04 μm, and a maximum roughnessheight Ry of the second end surface is between approximately 0.1 and 0.5μm.
 11. A method for increasing edge strength of a display panel, thedisplay panel comprising a first substrate, a second substrate and asealant, the sealant being disposed between the first substrate and thesecond substrate, the method comprising: providing the display panel;tilting the display panel so that the second substrate of the displaypanel and a horizontal plane form a tilt angle; grinding the secondsubstrate to form a grinding end surface on the second substrate whilethe display panel is tilted at the tilt angle; and polishing thegrinding end surface to form an end surface, wherein an arithmeticaverage roughness Ra of the end surface is between 0.001 and 0.04 μm,and a maximum roughness height Ry of the end surface is betweenapproximately 0.1 and 0.5 μm.
 12. A display panel, comprising: a firstsubstrate comprising a first outer surface, a first inner surface and afirst end surface, the first outer surface and the first end surfaceforming a first included angle therebetween; a second substrate disposedopposite to the first substrate and comprising a second outer surface, asecond inner surface and a second end surface, the second outer surfaceand the second end surface forming a second included angle therebetween;and a sealant disposed between the first inner surface and the secondinner surface, and comprising a sealant end surface between the firstend surface and the second end surface; wherein an arithmetic averageroughness Ra of the first end surface or the second end surface isbetween 0.001 and 0.04 μm, and a maximum roughness height Ry of thefirst end surface or the second end surface is between approximately 0.1and 0.5 μm.
 13. The display panel of claim 12, wherein the sum of thefirst included angle and the second included angle is equal to 180degrees.
 14. The display panel of claim 12, wherein the first includedangle is equal to the second included angle.
 15. The display panel ofclaim 12, wherein the first substrate further comprises alight-shielding area disposed between the first inner surface and thesealant.
 16. The display panel of claim 15, wherein the light-shieldingarea further comprises an outer end surface and an inner end surface,the outer end surface is connected to the first end surface or thesealant end surface, and the inner end surface is disposed opposite tothe outer end surface.
 17. A method for narrowing edges of a displaypanel, the display panel comprising a first substrate, a secondsubstrate, a sealant, an initial first photo spacer, a second photospacer and a liquid crystal layer, the initial first photo spacer andthe second photo spacer forming a trench at an edge of the firstsubstrate, the initial first photo spacer being placed outside thesealant and far from the liquid crystal layer, the second photo spacerbeing placed inside the sealant and next to the liquid crystal layer,the sealant and the liquid crystal layer being placed between the firstsubstrate and the second substrate, and the sealant being within thetrench, the method comprising: providing the display panel; andsimultaneously cutting the first substrate, the initial first sensingspacer and the second substrate to form a first photo spacer and an endsurface, the end surface going through the first substrate, the firstphoto spacer and the second substrate.
 18. The method of claim 17,wherein the cutting is to cut the first substrate, the initial firstsensing spacer and the second substrate at a tilt angle.
 19. The methodof claim 17, further comprising a step of polishing the end surface,wherein an arithmetic average roughness Ra of the end surface is between0.001 and 0.04 μm, and a maximum roughness height Ry of the end surfaceis between approximately 0.1 and 0.5 μm.
 20. A display panel,comprising: a first substrate; a second substrate disposed opposite tothe first substrate; a liquid crystal layer disposed between the firstsubstrate and the second substrate; a first photo spacer disposed on thefirst substrate and between the first substrate and the secondsubstrate; a second photo spacer disposed on the first substrate andbetween the first substrate and the second substrate, and the secondphoto spacer and the first photo spacer forming a trench therebetween;and a sealant disposed between the first substrate and the secondsubstrate and within the trench; wherein the first photo spacer isplaced outside the sealant and far from the liquid crystal layer, thesecond photo spacer is placed inside the sealant and next to the liquidcrystal layer, the first photo spacer and the first substrate and thesecond substrate at a corresponding position form an end surface goingfrom the first substrate, the first photo spacer and the secondsubstrate.
 21. The display panel of claim 20, wherein the first photospacer and the second substrate form a first gap, and the second photospacer and the second substrate form a second gap.
 22. A display panel,comprising: a first substrate comprising a first outer surface, a firstinner surface and a first end surface, the first outer surface and thefirst end surface forming a first included angle therebetween; a secondsubstrate disposed opposite to the first substrate, and comprising asecond outer surface, a second inner surface and a second end surface,the second outer surface and the second end surface forming a secondincluded angle therebetween; and a liquid crystal confined structuredisposed between the first inner surface and the second inner surface,and the liquid crystal confined structure having a liquid crystalconfined structure end surface disposed between the first end surfaceand the second end surface; wherein the first included angle is between90 and 110 degrees, and the second included angle is between 70 and 110degrees.
 23. The display panel of claim 22, wherein the liquid crystalconfined structure comprises a sealant.
 24. The display panel of claim22, wherein the liquid crystal confined structure comprises a firstphoto spacer, a second photo spacer and a sealant disposed between thefirst photo spacer and the second photo spacer.
 25. The display panel ofclaim 22, wherein the liquid crystal confined structure end surface isplaced at the first photo spacer.